Water leaks are a common problem associated with air conditioners, hot water heaters, washing machines, and various other water-dependent appliances used in buildings such as homes, townhouses, apartments, mobile homes, and offices. Unfortunately, water leaks are typically detected only after a substantial leak or a substantial accumulation of water has developed. Thus, it would be advantageous to have the benefit of an early-warning and prevention system for detecting these common water leaks before costly repairs become necessary to correct resulting damages and protect further damage therefrom.
Maintaining and protecting a commercial or residential setting can be difficult and costly. Conditions such as fires, gas leaks, etc. are a danger to the occupants and the structure. Other malfunctions, such as water leaks in plumbing, are not necessarily dangerous for the occupants, but can nevertheless cause considerable damage. In many cases, an adverse condition created by water leakage is not detected in its early stages when the damage and/or danger are relatively small. Water leaks are always inconvenient and may cause incidental damage to furniture, electrical equipment, and other property. Furthermore, this problem is compounded by the prevalence of aging appliances, aging water pipes, and deteriorated joints therein.
There have been many developments in the art seeking to detect water leaks occurring in water-related appliances and the like. A water detector may be an electronic device designed to detect the presence of water and provide an alert in time to limit or allow prevention of water damage. Prior art designs are generally comprised of a small cable or device that lies flat on a floor and relies on the electrical conductivity of water to decrease the resistance across two contacts. When sufficient water is present to bridge the contacts, the device sounds an audible alarm together with signaling. Such devices are useful in a normally occupied area with an infrastructure that has the potential to leak water, such as an HVAC, water pipes, drain pipes, vending machines, dehumidifiers, or water tanks. For instance, U.S. Pat. No. 5,188,143 discloses a water leakage detector sensitive to the presence of moisture and adapted for installation around a water vessel. The detector has an elongated, flexible sensing strip comprised of a pair of conductors separated by insulation. Each conductor includes an electrode coupled with a wire lead extending via a cable to an electrical plug. A circuit housing having an audible alarm operably connected to an electrical socket adapted to detachably connect with the plug is provided.
Although prior art water detectors utilize warning sounds to notify of a water leak and are equipped with a certain detection function in the event that the user is away from the home or commercial establishment, they are unable to immediately notify the user about the water leakage. Thus, by the time the user is aware of the water leakage, the water may have accumulated to a level to cause significant damage to the floor, carpet, interior decoration or furniture, resulting in expensive remodeling or handy work for the owner. In other words, such a conventional water leakage detection system with warning sounds is not of practical use if the user is not always present. Furthermore, the reliability of these water leak detection devices can be questionable because they rely on electronic means for sensing the presence of moisture or fluid. These devices are susceptible to not being triggered by a water leak because of a reliance on electronic or conductive means for sensing the presence of moisture or fluid. For example, U.S. Pat. No. 4,843,305 discloses an apparatus for sensing leaks in water pipes based upon the conductivity of spaced-apart pairs of insulated conductors which are wrapped around the pipe. Unfortunately, leaking water may not always establish contact with all exposed areas of the insulated conductors, or the leaking water may not adhere to the conductors, thereby failing to signal a leak. Additionally, corrosion or the loss of electricity or power from batteries provides another failure point. Similarly, U.S. Pat. No. 4,374,379 teaches a moisture sensing apparatus for pipes that also uses a pair of spaced-apart electrical conductors partially positioned in an elongated flexible insulator which is circumferentially affixed to such pipe. The partially exposed electrical connectors are oppositely disposed relative to the pipe. An alarm actuating circuit is interconnected with the conductors and configured to initiate the alarm when water bridges the spaced apart conductors. However, this apparatus is insensitive to small leaks where water droplets are unable to bridge the sensing electrode gap disposed on the opposite sides of the sensor assembly.
Furthermore, there exists leak detection devices that have electronic sensor elements, such as described above, that measure the conductivity of the water and use such a detection means to energize a solenoid or other such device to turn off an associated water valve. Unfortunately, the electronic circuitry adds cost and reduces reliability, as discussed above. It also requires the presence of electrical power to function. Thus, if a water leak were to occur coincidentally with an electrical power outage, such as may occur with a large storm, the valve will fail to accomplish its purpose unless auxiliary power is available.
There are several prior art devices that provide water shutoff protection utilizing a water sensor that changes physical properties when placed in contact with water, resulting in activation of a valve shutoff device. For instance, U.S. Pat. No. 2,798,503 utilizes a water softenable link that dissolves when coming into contact with water leaking from a water heater into an associated drip pan. As described, the cable attaching the water softenable link to the shutoff valve must be positioned directly beneath the shutoff valve so that the softenable link can be anchored in the drip pan. While appropriate for this installation, it would not provide the flexibility to be applicable on other applications. U.S. Pat. No. 3,920,031 describes a water shutoff device associated with a water heater application. The water detection means involves the use of a water-soluble material held in compression by a spring. The water detection means is placed in a drip pan that surrounds the base of the water heater such that, as water leaks from the faulty water heater, it will reach a level to dissolve the detection means, which in turn releases a spring driven valve that is plumbed into the water supply line of the water heater. U.S. Pat. No. 6,024,116 provides a water softenable latch that, when exposed to water, will release a valve mechanism from its open to closed state, thus turning off the water and gas supply in a water heater. Unfortunately, the installation of such shutoff devices described above requires intensive plumbing skills or would involve hiring a licensed plumber to comply with local building codes.
Thus, what is lacking in the art is a water leak detection and prevention device whereby the leak detector utilizes a water soluble sensor coupled with a water shut-off device to provide obstruction of incoming water through a water pipe using a spring-loaded plunger for use with clothes washing machines, dishwashing machines, toilets, sinks, refrigerators, or the like, that is easily installed and does not require electrical or battery power for operation.